[Synthesis]
Step c: Synthesis of intermediate 5,2-(4-bromo-2-methylphenyl)acetonitrile
1-Bromo-4-(bromomethyl)-3-methylbenzene (13.2 g, 50.1 mmol) was dissolved in DMF (65 mL). The reaction mixture was cooled to 0-5 °C, followed by addition of NaCN (3.66 g, 74.6 mmol) and water (8 mL). The reaction mixture was stirred at room temperature overnight. After completion of the reaction, water (170 mL) and saturated NaHCO3 solution (130 mL) were added, followed by hexane/Et2O (2:1, 150 mL) for extraction. The organic phase was separated and the aqueous phase was further extracted with hexane/Et2O (2:1, 3 x 150 mL). All organic phases were combined, washed with water (170 mL), dried over MgSO4, filtered and concentrated under reduced pressure to afford the target product 2-(4-bromo-2-methylphenyl)acetonitrile (9.76 g, 93% yield) as an orange oil.
1H NMR (300 MHz, chloroform-D) δ: 7.40-7.32 (2H, m), 7.23 (2H, d, J = 8.2 Hz), 3.61 (2H, s), 2.32 (3H, s). |